1. Field of the Invention
The present invention relates to an exposure apparatus and, more particularly, to an exposure apparatus for exposing a circuit pattern of a semiconductor device, liquid crystal display device, etc. to a prescribed substrate, etc. The invention also concerns an exposure apparatus for exposing a prescribed circuit pattern, etc. to a prescribed substrate, etc. in order to manufacture a high-density print circuit substrate of a BGA substrate, CSP substrate, etc.
2. Description of the Related Art
An exposure apparatus for optically exposing a circuit pattern of a semiconductor device, liquid crystal display device, etc., which is what is called xe2x80x9ca stepperxe2x80x9d, has hitherto been generally put to practical use.
An ordinary exposure apparatus is generally constructed in such a form wherein, for example, a so-called xe2x80x9creticulexe2x80x9d becoming an original substrate, which has a circuit pattern formed on a glass substrate (glass mask), is prepared; with respect to this reticule an illumination light is irradiated and this beam of light is passed through a projection optical system to thereby cause a circuit pattern image reduced or increased in size to be formed; and the resulting circuit pattern image is exposed to a substrate such as a wafer or glass substrate that has coated thereon a photo-resist. However, in this exposure apparatus, it is difficult to form the reticule becoming an original substrate by the use of a glass substrate and at a low cost.
On this account, an apparatus wherein, using a display device such as a liquid crystal device (Liquid Crystal Device: LCD), etc. in place of a glass substrate serving as the conventional reticule, the circuit pattern is caused to be displayed, and the resulting arrangement is used as the original substrate has variously been proposed in, for example, Japanese Patent Application Laid-Open Nos. 9-17719 and 11-45851.
The apparatus disclosed in the above-described Japanese Patent Application Laid-Open Nos. 9-17719 and 11-45851 is constructed into a form wherein, in place of the reticule consisting of a glass substrate, etc. having a circuit pattern formed thereon, a circuit pattern, etc. such as design data, etc. is displayed on the display part of a single liquid crystal panel, consisting of a display device or the like such as a liquid crystal display device (LCD). And a circuit pattern image obtained by reducing or increasing the size of the circuit pattern through a projection optical system is projected onto a substrate, and thereby a desired circuit pattern is optically exposed.
However, in the apparatus disclosed in any of the above-described Japanese Patent Application Laid-Open Nos. 9-17719 and 11-45851, a single liquid crystal panel is used. In order to project a clearer circuit pattern image, the liquid crystal panel is needed to have a higher resolution. But, the resolution of the liquid crystal panel depends upon the number of pixels per unit area of the display devices forming the liquid crystal panel. However, a limitation is imposed upon the increase in the number of pixels.
Namely, in the case of using a single liquid crystal panel, in case the widening of the display area attempts to be ensured without deteriorating the resolution of the liquid crystal panel, the manufacturing cost of the liquid crystal panel tends to increase very much. Also, when making small the display area of each of the individual display devices, there is a limitation.
Accordingly, for example, in the case of projecting a finely designed circuit pattern such as an IC or LSI onto the substrate, in the apparatus using the display means comprised of a single liquid crystal panel, etc., ensuring a sufficient value of resolving power leads to an increase in the cost compared to the conventional case where using a glass substrate, etc. as the reticule. Therefore, there is the problem that realizing such resolving power easily and at a low cost is difficult.
On the other hand, an exposure apparatus wherein in order to manufacture a high-density substrate, etc. such as a BGA substrate or CSP substrate a prescribed circuit pattern, etc. is exposed to a prescribed substrate material has hitherto been generally put to practical use.
When manufacturing the high-density printed substrate, the following steps are generally performed. For example, using data based on the use of a circuit pattern, an exposure printing mask is produced. This mask is set in the exposure apparatus, whereby prescribed exposure is performed with respect to a prescribed substrate material. Thereafter, prescribed steps of processing such as developing of the already exposed substrate material, etching thereof, etc. are performed.
However, in recent years, when manufacturing a high-density printed substrate, etc., it has been demanded to enable manufacturing various different kinds of printed substrates such as a BGA substrate or CSP substrate with the use of the same manufacturing apparatus. It is inefficient when each time the kind of the printed substrates is different a new mask is produced.
Under the above-described existing circumstances, various proposals for manufacturing a desired high-density printed substrate, etc. without using the exposure printing mask, have in recent years been made in, for example, Japanese Patent Application Laid-Open No. 7-35994.
The apparatus disclosed in Japanese Patent Application Laid-Open No. 7-35994 uses, in place of the step of producing an exposure printing mask and an exposure step of exposing a desired circuit pattern, according to this exposure printing mask, means for directly depicting a desired circuit pattern with respect to a substrate to be manufactured by the use of a laser beam according to prescribed data representing a desired circuit pattern. And, in the apparatus of the above Publication, disclosed is the following. In order to realize an increase in the speed of manufacture, a plurality of laser beams are provided. Correspondingly to these laser beams, the entire desired circuit pattern to be depicted is divided into a plurality of regions. And, the respective divided regions are depicted in parallel using a plurality of the laser beams.
The problem with the apparatus disclosed in Japanese Patent Application Laid-Open No. 7-35994 was that the construction became very complex.
A first object of the present invention is to provide an exposure apparatus that utilizes an image display, in which there is ensured a wider region of display area using a plurality of liquid crystal panels each having a general display size, etc. without deteriorating the resolution, and thereby enables forming a sufficiently high resolution of image of even a finely designed circuit pattern onto a substrate.
A second object of the invention is to provide an exposure apparatus that enables ensuring an inexpensive and reliable exposure operation to be performed.
A third object of the invention is to provide an exposure apparatus that is constructed without using an exposure printing mask and that can easily cope with various kinds of sizes of substrates, various circuit patterns, etc., thereby enabling realizing higher availability.
A fourth object of the invention is to provide an exposure apparatus that is simpler in construction and can realize an increase in speed.
Briefly explaining, the first invention, an exposure apparatus is adapted to project one unit of circuit pattern onto the surface of a resist on a substrate, which exposure apparatus comprises a division processing section that, in case one unit of circuit pattern is divided into a plurality of regions, divides it so that adjacent ones of the regions may partly overlap each other, an exposure section that is equipped with a plurality of optical systems each projecting one divided region of a plurality of the divided regions onto the resist surface on the substrate, and a controller means that, while causing duplex regions of the adjacent regions to overlap each other on the resist surface on the substrate, causes a plurality of the divided regions to be simultaneously projected onto the resist surface by the exposure section to thereby cause an image of one unit of circuit pattern to be formed on the resist surface of the substrate.
According to a second aspect the, invention provides an exposure apparatus that comprises a light source that radiates an illumination light for performing exposure, a modulator which modulates the spatial intensity distribution of the illumination light from the light source according to code data produced from a design circuit pattern, a plurality of exposure units each of which is constructed in such a way as to include an optical system for projecting the illumination light the spatial intensity distribution of which has been modulated, means for properly disposing each of the individual exposure units according to the code data that is obtained correspondingly to the disposition of the substrate, and a correction processor which performs correction processing with respect to the code data representing the design circuit pattern so that a pattern image that is formed according to the code data may be projected onto the surface of exposure in a state of its being proper on this surface of exposure.
These and other objects and the advantages of the invention will become apparent from the following detailed explanation.
According to the first aspect of the invention, it is possible to provide an exposure apparatus that, utilizing the image display that ensures the procurement of a wider region of display area without deteriorating the resolution by the use of a plurality of liquid crystal panels each having a general display size, enables even a finely designed circuit pattern to have formed on the substrate an image that has a sufficiently large value of resolution, and that enables ensuring the performance of an inexpensive, reliable exposure operation.
Also, according to the second aspect of the invention, it is possible to provide an exposure apparatus which does not use an exposure printing mask, and that can easily cope with various kinds of substrate size, circuit pattern, etc. to thereby realize a high level of general applicability and that can realize a simpler construction and the increase in an operational speed of the apparatus.